Search results for " IS"
showing 10 items of 5661 documents
Barbegal carbonate imprints give a voice to the first industrial complex of Europe
2019
International audience; The watermill complex of Barbegal is one of the first industrial complexes in the world, and one of the largest such installations known from antiquity. It has been studied through excavations and what is known about the complex, its history and purpose, is based on the remaining stonework of mills and water installations, since no traces of the woodwork or machinery of the mills have been preserved. The archaeological museum in Arles, however, stores 142 pieces of carbonate that formed on the woodwork of the mills. We studied this material by analysis of the shape of the fragments and of stable isotopes and crystallographic fabric of selected carbonate samples. This…
Effects of cooking on mollusk shell structure and chemistry: Implications for archeology and paleoenvironmental reconstruction
2016
Mollusk shells excavated from archeological sites have been used to reconstruct paleoenvironment, human foraging, and migratory patterns. To retrieve information on past environment or human behavior, chemical signatures such as oxygen stable isotopes (δ18Oshell) are analyzed. Shell archeological remains usually represent food waste. Thermal treatments such as boiling and roasting may influence shell structure and biochemical composition. However, little is known about the relationship between changes at macro-, microstructural and chemical levels. This work is a calibration study on modern Phorcus (Osilinus) turbinatus shells. A simulation of two different cooking methods (boiling and roas…
Stone-age subsistence strategies at Lake Burtnieks, Latvia
2018
Abstract Zvejnieki, on Lake Burtnieks in northeastern Latvia, is the largest known prehistoric cemetery in the eastern Baltic; > 300 inhumations, most dating to c.7000–3000 cal BC, have been excavated. Archaeozoological and artefactual evidence from graves and nearby settlement layers show that throughout this period, the community depended on wild resources for subsistence, with a particular emphasis on fishing. Dietary stable isotopes (δ 15 N and δ 13 C) from human remains show significant dietary variation within the Zvejnieki population, in terms of access to and dependence on freshwater and marine species (Eriksson 2006); we provide new stable isotope data for another 13 individuals. E…
New data about the landscape of the first occupation of Mallorca: Coval Simó (Escorca, Mallorca)
2020
The Coval Simó shelter provides some of the oldest evidence for settlement on the island of Mallorca and the Balearic archipelago. It also has the peculiarity of being a habitat in a mountain area, so that the human groups that settled there had to adapt their agricultural and farming system to this environment. The plant remains (wood charcoal and seeds) recovered in the occupation levels allow us to address these issues, since they are the result of the different activities developed in this cavity: fuel for domestic activities, food for livestock, etc. The results of this study show that between the III and II millennium cal BC, an agricultural system based on livestock and cereal farmi…
No Age Trends in Oak Stable Isotopes
2020
Community replacement of neritic carbonate organisms during the late Valanginian platform demise: a new record from the Provence Platform.
2012
24 pages; International audience; The Valanginian is marked by amajor platform demise inducing a hiatus in the northern Tethyan neritic carbonate record from the top of the lower Valanginian to the lower Hauterivian. New biostratigraphic and chemostratigraphic data from the Ollioules section (Provence Platform, southern France) are presented here, demonstrating that a large part of the upper Valanginian is preserved in an inner platform environment. The thick, upper Valanginian, aggrading carbonate succession is observed in an aborted rift domain, implying relatively low subsidence. In this context, a relatively long-term sea-level rise was required to sustain a keep-up style of carbonate p…
The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems
2018
Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-sample” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxyg…
Detailed record of the mid-Oxfordian (Late Jurassic) positive carbon-isotope excursion in two hemipelagic sections (France and Switzerland): A plate …
2007
14 pages; International audience; The Oxfordian (Late Jurassic) was a time of widespread change in Jurassic marine (carbonate) sedimentation patterns. A marked positive excursion in δ13C is dated as Middle Oxfordian in age. In this study we investigate if changes in carbonate sedimentation coincided with altered carbon cycling and climate. We use C-isotope records as a proxy for the evolution of the carbon cycle and compare δ13C-trends with the evolution of sedimentation in a segment of the opening Tethys seaway. One of the studied sections is located in the Subalpine basin of France (Trescléoux and Oze), the other in the Swiss Jura mountains (Liesberg). Carbon-isotope stratigraphy of carbo…
A low seasonality scenario in the Mediterranean Sea during the Calabrian (Early Pleistocene) inferred from fossil Arctica islandica shells
2017
Understanding past seasonal temperature variability in the ocean is essential to evaluate the effects of future climate change on marine ecosystems. Here, we estimate seasonal water temperature amplitudes from stable oxygen isotope (δ18Oshell) values of fossil shells of Arctica islandica (assuming δ18Owater= + 0.9 ± 0.1â° V-SMOW). Specimens were collected from three Pleistocene successions (Emilian and Sicilian substages of the Calabrian) in Central and Southern Italy (i.e., Rome, Lecce and Sicily). Biostratigraphic analyses from Rome Quarry deposits indicate an age between 1.6 and 1.2 Ma, whereas Sicily and Lecce successions are slightly more recent (between 1.1 and 0.62 Ma). Prior to …
Bioavailable 87Sr/86Sr in different environmental samples — Effects of anthropogenic contamination and implications for isoscapes in past migration s…
2012
(87)Sr/(86)Sr reference maps (isoscapes) are a key tool for investigating past human and animal migrations. However, there is little understanding of which biosphere samples are best proxies for local bioavailable Sr when dealing with movements of past populations. In this study, biological and geological samples (ground vegetation, tree leaves, rock leachates, water, soil extracts, as well as modern and archeological animal teeth and snail shells) were collected in the vicinity of two early medieval cemeteries ("Thuringians", 5-6th century AD) in central Germany, in order to characterize (87)Sr/(86)Sr of the local biosphere. Animal tooth enamel is not appropriate in this specific context t…